Background: Whipple's disease is a systemic infection that sometimes is associated with cardiac manifestations. The diagnosis of Tropheryma whipplei endocarditis is still the result of chance because there are no diagnostic criteria and clinical signs are often those of cardiac disease rather than infection.
Case presentation: Culture-negative endocarditis was suspected in a non-febrile 77-year-old French woman from North France with a history of a graft replacement 4 years prior. Positron emission tomography revealed intense fluorodeoxyglucose uptake around the metal ring of the aortic graft. The valve was replaced, and T. whipplei was detected in a valve sample by molecular assays. Immunohistochemical staining of the valve for T. whipplei was also positive.
Conclusion: The localization of infectious foci by positron emission tomography and systematically testing valve specimens for T. whipplei are promising for diagnosing Whipple's disease.